Security Resilience

CVE-2023-20095

Cisco Adaptive Security Appliance Software 9.12.1 … 9.8.4.8

Published
01 November 2023
Modified
11 August 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0065 50th percentile
Risk Priority 62 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-20095 is a high-severity Missing Release of Resource after Effective Lifetime (CWE-772) vulnerability in Cisco Adaptive Security Appliance Software. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique LSASS Memory (T1003.001); ranked at the 50th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.…

more

This vulnerability is due to improper handling of HTTPS requests. An attacker could exploit this vulnerability by sending crafted HTTPS requests to an affected system. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a DoS condition.

CWE(s)
CWE-772NVD-CWE-noinfo

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
attack.mitre.org →
T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1003.005 Cached Domain Credentials Credential Access
Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
T1003.007 Proc Filesystem Credential Access
Adversaries may gather credentials from the proc filesystem or `/proc`.
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20481Same product: Cisco Adaptive Security Appliance Software
CVE-2024-20493Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20082Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20106Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20013Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20105Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20021Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20014Same product: Cisco Adaptive Security Appliance Software
CVE-2023-20086Same product: Cisco Adaptive Security Appliance Software
CVE-2026-20015Same product: Cisco Adaptive Security Appliance Software

Affected Assets

cisco
adaptive security appliance software
9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1
cisco
secure firewall threat defense
6.2.3, 6.2.3.0, 6.2.3.1, 6.2.3.10, 6.2.3.11

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-10 Network Disconnect
addresses: CWE-772

Ensures network resources are released once the session ends or becomes inactive, closing the window for missing-release weaknesses.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

DE.CM-09 partial match
blocks

Runtime monitoring may surface resource-exhaustion symptoms but does not address release logic.

ID.AM-08 partial match
blocks

Lifecycle management explicitly requires handling resources through end-of-life including release.

PR.IR-04 partial match
blocks

Capacity monitoring can detect exhaustion caused by unreleased resources but does not prevent the root defect.

PR.PS-06 partial match
blocks

Secure SDLC practices directly prevent missing resource-release defects during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
degrades

Explicit information-deletion requirements directly address timely release of resources after use.

References